Hi Mark, On Mar 13, 2009, at 3:54 AM, Mark Spezzano wrote:

I was wondering what the best way to implement Natural number would be. Is there a package which already does this?

there are two packages on Hackage that implement natural numbers using algebraic datatypes: 'numbers' has a module Data.Number.Natural that implements them in "unary" notation (zero and successor), 'nat' has Data.Number.Nat that uses a binary encoding. Cheers, Sebastian